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Stock-Based Compensation - Narrative (Details) $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
	May 15, 2018 shares	Feb. 28, 2025 shares	Jun. 30, 2025 shares	Jun. 30, 2024	Sep. 30, 2025 USD ($) performanceCondition shares	Dec. 31, 2024 shares	Dec. 31, 2023 shares	May 13, 2023 shares
Stock-Based Compensation
Inducement stock options granted to new employees (in shares)					475,754
Inducement total authorized for grant (in shares)		1,000,000
Common stock options
Stock-Based Compensation
Unrecognized compensation expense related to unvested stock options \| $					$ 150.8
Unvested RSUs
Stock-Based Compensation
Unrecognized compensation expense related to unvested RSU awards \| $					$ 146.9
Performance Stock Units
Stock-Based Compensation
Unvested PSUs outstanding (in shares)					0
Number of performance conditions \| performanceCondition					2
Service period					3 years
Potential award payout				250.00%
Issued (in shares)					660,466
Stock-based compensation expense \| $					$ 10.3
2019 Incentive Plan
Stock-Based Compensation
Shares of common stock, maximum authorized for issuance (in shares)								13,750,000
Number of additional shares authorized (in shares)			10,000,000			3,000,000	10,500,000
Shares available for grant (in shares)					11,919,435
2025 Inducement Plan
Stock-Based Compensation
Number of shares granted (in shares)					253,004
Options outstanding (in shares)					114,780
2018 ESPP
Stock-Based Compensation
Shares of common stock, maximum authorized for issuance (in shares)	1,000,000
Number of additional shares authorized (in shares)	1,200,000
Percentage of outstanding shares	2.00%